As a method for inspecting a pattern formed on the surface of a structure, the die-to-die method and die-to-database method are known.
These inspection methods use inspection data obtained by imaging a magnified optical image of the pattern on the light receiving surface of e.g. a CCD sensor (charge coupled device image sensor).
However, recently, pattern miniaturization has advanced, and often made it impossible to optically resolve the pattern. Thus, inspection of such an optically unresolvable pattern may fail to achieve sufficient inspection sensitivity.